I notice in twenty eleven the recommended header image size is:
mages should be at least 1000 pixels wide. Suggested width is 1000 pixels. Suggested height is 288 pixels.
I was wondering why so wide and why so tall?
At my site (http://lerner.net) I made my banner the recommended size but it takes up an awful lot of space. Especially when viewing on an iPad in landscape mode.
Also, the two columns, content and sidebar, don't match the ends of the 1000 pixel width. Wouldn't it look nicer if they did?